Estradiol

Estradiol (17-beta estradiol) is a sex hormone. Labelled the "female" hormone but also present in males it represents the major estrogen in humans. Critical for sexual functioning, estradiol also supports bone growth. more...

Synthesis

Estradiol, like other sex steroids, is derived from cholesterol. After side chain cleavage and either utilizing the delta-5 pathway or the delta-4 pathway androstenedione is the key intermediary. Androstendione is either converted to testosterone which in turn undergoes aromatization to estradiol, or, alternatively, androstendione is aromatized to estrone which is converted to estradiol.

Conversion of testosterone to estradiol:

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